Goodwill and Other Intangible Assets (Goodwill) (Details)
$ in Millions
Mar. 31, 2016
|Goodwill [Roll Forward]|
|Goodwill, Beginning Balance||$ 14,345|
|Goodwill, Ending Balance||$ 14,345|
Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
Reference 1: http://www.xbrl.org/2003/role/presentationRef